I've also discovered this in the field of Biology. A lot of biomolecular and genetics research is now done in China, and you'd be hard-pressed to find a paper that doesn't have a majority Chinese scientists involved.
I assume this is where the "Chinese spies steal US technology and research from universities" conspiracy theory comes from. A Chinese and Western university collaborate. The Western university gets all the credit in the west. A couple years later, the Chinese university actually advances the research even further. The Western media then say it was the Western university that started the research, and the Chinese university has stolen it.